Clinical phenotypes in persons with hip osteoarthritis and prognostic factors of outcome following total hip arthroplasty (R-11552)

Osteoarthritis (OA) is a leading cause of pain and disability worldwide. The hip joint is clinically the second most affected location of OA, only preceded by the knee joint. Each year, more than 40 million prevalent cases and more than 2 million incident cases of hip OA are reported worldwide. The global prevalence and incidence are expected to increase considerably in the upcoming decades, as a result of the aging population and an increasing prevalence of risk factors such as obesity and a sedentary lifestyle. Total hip arthroplasty (THA) is a cost-effective procedure in patients with end-stage hip OA. However, previous studies have reported that 8% of patients are dissatisfied with the outcome following THA, and up to 23% of patients report long-term pain following THA. Furthermore, over 30% of patients report limitations in activities of daily living two years after THA. Nevertheless, the mean utilization rate of hip implants increases significantly, and the growth rate is considerably higher in younger, working-age patients. The goal of this project is to understand and predict the outcomes after THA in patients with hip OA. Therefore, the aims are to identify prognostic factors for outcome after THA in persons with hip osteoarthritis and to identify clinical phenotypes in patients with hip OA before and after THA. First of all, a systematic review on prognosis in patients with THA will be conducted. The difference in prognosis cannot be entirely explained by body functions and structures, surgery itself or preoperative activity limitations. Contextual factors might add value to the prognosis of outcome in the ICF domain activity and participation. Therefore, this systematic review aims to determine the contextual factors, situated within the ICF framework, associated with activity limitations and participation restrictions following total hip arthroplasty (THA) in persons with hip osteoarthritis. The second phase of this project consists of a longitudinal prospective prognostic cohort study (HIPPROCLIPS). This study has two major goals, (1) to identify clinical phenotypes - based on a set of biopsychosocial variables - in patients with hip OA and after THA, and (2) to identify prognostic factors for outcome after THA, with focus on pain-related fear avoidance and perceived injustice. Therefore, patients with hip OA on the waiting list for THA will be recruited in 'Ziekenhuis Oost-Limburg' in Genk, and 'de Heuppraktijk' in Herselt. These patients will be investigated on a set of biopsychosocial variables preoperatively, immediately postoperatively (1st, 3rd, 5th and 7th day), and six weeks, three months and twelve months postoperatively. The test protocol exists of sociodemographic information, pain-related variables, psychosocial questionnaires (FACS, TSK, IEQ, HADS, GSES, GO-SSS), strength tests of the hip muscles (MicroFet 2), quantitative sensory testing (QST) and performance-based measures (30s chair test, stair climb test, 40m fast paced walk test). Outcome variables are situated in the ICF domain activity and participation (HOOS-ADL, HOOS-sports/recreation, PSFS, performance-based measures), quality of life (HOOS-QoL, SF-36), pain and symptoms (HOOS-pain/symptoms, NPRS), global perceived effect (GEE) and satisfaction (NRS). Descriptive statistics, correlation analyses, cluster analysis, and polynomial regression analysis will be performed.

Keywords:activities and participation, clinical phenotypes, Hip osteoarthritis, pain-related fear avoidance, perceived injustice, prognostic factors, total hip arthroplasty (THA)

Disciplines:Musculo-skeletal systems, Rehabilitation sciences, Orthopaedic surgery